1. Field of the Invention
The present invention relates to an X-ray analyzer and a mapping method which are suitable for performing an X-ray mapping analysis on a surface of a sample through, for example, a fluorescent X-ray analysis.
2. Description of the Related Art
A fluorescent X-ray analysis is used to perform a qualitative analysis or a quantitative analysis of a sample by irradiating the sample with an X-ray emitted from an X-ray source to detect, with an X-ray detector, a fluorescent X-ray which is a characteristic X-ray emitted from the sample, and by obtaining a spectrum from energy of the fluorescent X-ray. The fluorescent X-ray analysis enables the non-destructive and quick analysis of the sample, and therefore the fluorescent X-ray analysis is widely used in manufacturing process management, quality control, or the like. In recent years, precision and sensitivity have been increased in the X-ray analysis, which enables trace measurement. Accordingly, there is expected the diffusion of the fluorescent X-ray analysis as an analysis technique of performing detection especially of a harmful substance contained in a material, a composite electronic component, or the like (for example, Japanese Unexamined Patent Application Publication Nos. 2006-119108 and 2007-163183).
As analysis techniques in the fluorescent X-ray analysis, there are a wavelength dispersive method of splitting a fluorescent X-ray by an analyzing crystal to measure a wavelength and an intensity of the X-ray, an energy dispersive method of detecting a fluorescent X-ray with a semiconductor detector without splitting the fluorescent X-ray to measure an energy and an intensity of the X-ray with a pulse height analyzer, and the like.
Conventionally, for example, Japanese Unexamined Patent Application Publication Nos. 1992-175647, 1999-264805, and 2009-300232 propose an X-ray analyzer including an X-ray tube for irradiating a sample with an X-ray, an X-ray detector for detecting a fluorescent X-ray generated from the sample irradiated with the X-ray, a pulse processor for discriminating an element contained in the sample and its intensity based on an output of the X-ray detector, a computer to which a signal transmitted from the pulse processor is input, an image processing device for processing an output of the computer to display a distribution of an X-ray intensity in a two-dimensional image, and imaging means for imaging an optical observation image which corresponds to an image of the x-ray intensity.
An X-ray mapping analysis has been performed in order to detect a harmful substance contained in, for example, a material or a composite electronic component. Up to now, even when an X-ray intensity distribution of a focused element, for example, a harmful substance, is presented, a reference for defining a normal intensity region in the intensity distribution is not apparently specified and it is difficult to determine whether or not a detected position is really a position to be compared.